Bill Steffen's Summer 2011 forecast

GRAND RAPIDS, Mich. (WOOD) - Predicting summer weather isn't just about severe weather. You also want to know how many barbecue and beach days you'll see this season.

Severe Weather

Within three days in April, more than 250 tornadoes ripped apart towns and lives in 15 different states. From Arkansas to Western Ohio, between now and early June, there will likely be an unprecedented number of intense storms and tornadoes.

So far in West Michigan, this Spring's cool temperatures have kept most of the dangerous storms farther south. But as the temperature rises, so does our risk.

That's when, I believe, we'll see a significant number of severe storms, even tornadoes, in southern Michigan. South of a line between New Buffalo and Saginaw is where the threatening storms will most likely hit.

That increased risk is due partly to La Nina , a phenomenon characterized by cooler ocean temperatures along the Equator which pushes Tornado Alley east into the Missippi and Ohio valleys.

But by mid-June, our tornado threat will become less likely. Then we'll settle into an average storm season for the rest of the summer.

Heat and Rain

This summer, I'm calling for near-normal levels of both sun and rain. While more than average rain will fall early in the season, you should see less than average rain in the last half of the summer.

Temperatures should be close to average.

For a point of reference, the average high in July in West Michigan is in the low 80s. Consider these comparisons:

• In July 2009: average temperature was 4 degrees cooler than normal
• In July 2010: average temperature was 4 degrees warmer than normal.
• Prediction July 2011: average temperature 0.2 degrees below normal.

There won't be any extended heat waves, but there will be six to nine days of 90 degree temperatures - an average number for us.

The sun won't shine quite as often on your beach trips early this summer, but it won't be overly dreary.

On average, we see 62% of available sunshine during West Michigan summers.

• In 2009: there was 63% of sunshine
• In 2010: there was 71% of sunshine
• Prediction 2011: there will be 62% of sunshine.

That's considered an average West Michigan summer.

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